2009 Vol. 17, No. 5

论文
A majority of the Quaternary glacial deposits in China belong to either coarse-grained soil (erratic stone soil) or gravel soil. However, the engineering properties are different for glacial deposits in different areas or forming by different processes in a same area. It is because of the complex material composition and fabric characteristics of the deposits. The stability of geological bodies and geo-hazard susceptibilities are also significantly dissimilar. The existing relevant standards of engineering classification are not suitable to the need of future investigation on engineering geology and geo-hazards of glacial deposits. The field investigations and laboratory tests have shown that the glacial deposits have the following characteristics: inhomogeneity in particle size, dual elements in fabric, out-of-order and cementation in structure, etc. All the above characteristics have some closed relationships to the engineering properties of glacial deposits. In this paper, the engineering geological classification for the glacial deposits is discussed. A two-level classification scheme is presented and includes the evaluation of cementation, meso-structure and composition size. The schem can be considered as a guide to engineering practice and character study of the glacial deposits. A majority of the Quaternary glacial deposits in China belong to either coarse-grained soil (erratic stone soil) or gravel soil. However, the engineering properties are different for glacial deposits in different areas or forming by different processes in a same area. It is because of the complex material composition and fabric characteristics of the deposits. The stability of geological bodies and geo-hazard susceptibilities are also significantly dissimilar. The existing relevant standards of engineering classification are not suitable to the need of future investigation on engineering geology and geo-hazards of glacial deposits. The field investigations and laboratory tests have shown that the glacial deposits have the following characteristics: inhomogeneity in particle size, dual elements in fabric, out-of-order and cementation in structure, etc. All the above characteristics have some closed relationships to the engineering properties of glacial deposits. In this paper, the engineering geological classification for the glacial deposits is discussed. A two-level classification scheme is presented and includes the evaluation of cementation, meso-structure and composition size. The schem can be considered as a guide to engineering practice and character study of the glacial deposits.
Gravitational collapse, brittle failure and wedge falling are key geological problems that occurred during the construction of a rock tunnel at Jinping Ⅱ hydroelectric power station. The gravitational collapse mainly occurred in the Ⅳ and Ⅴ rock mass. The brittle failure mainly occurred in the Ⅰ and Ⅱ rock mass. The wedges falling mainly occurred in the Ⅱ, Ⅲ and Ⅳ rock mass. Three failure modes are common in the rock tunnel. They would bring about severe danger for workers and construction equipments , and greatly affect the construction schedule. This paper analyzes the geological causes of the threefailure modes and puts forward corresponding excavating and supporting measures. The proposed measures obtained favorable engineering results. Gravitational collapse, brittle failure and wedge falling are key geological problems that occurred during the construction of a rock tunnel at Jinping Ⅱ hydroelectric power station. The gravitational collapse mainly occurred in the Ⅳ and Ⅴ rock mass. The brittle failure mainly occurred in the Ⅰ and Ⅱ rock mass. The wedges falling mainly occurred in the Ⅱ, Ⅲ and Ⅳ rock mass. Three failure modes are common in the rock tunnel. They would bring about severe danger for workers and construction equipments , and greatly affect the construction schedule. This paper analyzes the geological causes of the threefailure modes and puts forward corresponding excavating and supporting measures. The proposed measures obtained favorable engineering results.
Erosion of river is the most important factor for occurrence of geo-hazards in Quaternary weak strata. This paper examines the bank slopes of Moxi Platform and carefully considers the internal relations between the river and the geo-hazards. It is based on the analysis of surveying geo-hazards in the bank slopes. It further evaluates the effect of environmental factors especially, the factors related with erosion of river, on stability of the bank slopes. Furthermore, the paper selects the highly related environmental factors to calculate the geo-hazard susceptibility map at the site. The results show that five factors including the curve of river, the river discharge, the grade of bank slope, the width of riverbed, and the width of bank slop are well contributed to the occurrence of geo-hazards. The geo-hazard susceptibility map predicted using a logistic model with the parameters can better illuminate the present and future features of the geo-hazards distribution. Based on the findings, the paper recommended preliminary suggestions for preventing geo-hazards at the Moxi platform. Erosion of river is the most important factor for occurrence of geo-hazards in Quaternary weak strata. This paper examines the bank slopes of Moxi Platform and carefully considers the internal relations between the river and the geo-hazards. It is based on the analysis of surveying geo-hazards in the bank slopes. It further evaluates the effect of environmental factors especially, the factors related with erosion of river, on stability of the bank slopes. Furthermore, the paper selects the highly related environmental factors to calculate the geo-hazard susceptibility map at the site. The results show that five factors including the curve of river, the river discharge, the grade of bank slope, the width of riverbed, and the width of bank slop are well contributed to the occurrence of geo-hazards. The geo-hazard susceptibility map predicted using a logistic model with the parameters can better illuminate the present and future features of the geo-hazards distribution. Based on the findings, the paper recommended preliminary suggestions for preventing geo-hazards at the Moxi platform.
During the dam base excavation of Xiaowan Hydropower Station, intensive unloading and relaxation happened to the superficial rock mass. Main types of the phenomena included crack slip, opening and development, in addition relaxation from new fracture. The latter mainly showed onion skin phenomenon, plate fracture phenomenon and rock burst phenomenon. Experiment results showed that slightly weathered rock nearby excavation surface was hard-extremely hard rock. But it had clear initial damage, and its critical stress ranged from 5.2 to 12.4MPa. Its tension strength changed from 3 to 6MPA. This was the material base on intensive unloading and relaxation of superficial dam base rock; Stress concentration from explosion excavation of dam base surface and effect from explosion were the lithology conditions of intensive unloading and relaxation of dam base rock. During the dam base excavation of Xiaowan Hydropower Station, intensive unloading and relaxation happened to the superficial rock mass. Main types of the phenomena included crack slip, opening and development, in addition relaxation from new fracture. The latter mainly showed onion skin phenomenon, plate fracture phenomenon and rock burst phenomenon. Experiment results showed that slightly weathered rock nearby excavation surface was hard-extremely hard rock. But it had clear initial damage, and its critical stress ranged from 5.2 to 12.4MPa. Its tension strength changed from 3 to 6MPA. This was the material base on intensive unloading and relaxation of superficial dam base rock; Stress concentration from explosion excavation of dam base surface and effect from explosion were the lithology conditions of intensive unloading and relaxation of dam base rock.
Active fault zones in Qinghai Province have their own distribution and kinematic characteristics under the pushing function of the Indian plate. This paper is based on the twenty-four active faults in the Province. Most of them are extended to NWW and sinistral strike-slip fault zones. The active fault zones which are extended to the NNW fault zones are dextral strike-slip and have the anti-clockwise direction characteristic. Mang'ai to Yousha mountain active fault have the highest vertical velocity. It may be caused by the crushing stress of the sinistral strike-lip of the Altun active fault zone and the pushing function of the Indian plate. Tecto-genesis of Miocene is the cause of the basic tectonic landform in Qinghai province. The up-lift of north Qinghai-Tibet Plateau is mainly located in west Qaidam and Qilian mountain area. The distribution of the extrusion stress register as the north and south part is more intense than the middle part. The east part is more intense than the west part. Active fault zones in Qinghai Province have their own distribution and kinematic characteristics under the pushing function of the Indian plate. This paper is based on the twenty-four active faults in the Province. Most of them are extended to NWW and sinistral strike-slip fault zones. The active fault zones which are extended to the NNW fault zones are dextral strike-slip and have the anti-clockwise direction characteristic. Mang'ai to Yousha mountain active fault have the highest vertical velocity. It may be caused by the crushing stress of the sinistral strike-lip of the Altun active fault zone and the pushing function of the Indian plate. Tecto-genesis of Miocene is the cause of the basic tectonic landform in Qinghai province. The up-lift of north Qinghai-Tibet Plateau is mainly located in west Qaidam and Qilian mountain area. The distribution of the extrusion stress register as the north and south part is more intense than the middle part. The east part is more intense than the west part.
It presents results of detailed investigation and drilling at the landslide. The results indicate that the special loess provides the material foundation for the formation of the landslide. Secondly, the slope relief, consequent slope structure, loess joints and so on provide the boundary conditions for the landslide instability. Next, human activities and precipitation and so on are the predominant e inducing factors for the instability. The various factors are complement to each other to lead to the development and taking place of the landslide. Based on the above results,this paper uses the SARMA and FLAC methods to calculate and simulate the stability extent of the landslide. The analysis of soil body stress and calculation o the factor of safety factor for the landslide show that although the landslide is in a stable state as a whole, there is the possibility for a partial instability of landslide at the left side of front edge. This analysis result is basically in accordance to the result of the field investigation result . But, in the saturated state, the natural and seismic state, the saturated and seismic state, the probability for a whole instability of the landslide is high. It presents results of detailed investigation and drilling at the landslide. The results indicate that the special loess provides the material foundation for the formation of the landslide. Secondly, the slope relief, consequent slope structure, loess joints and so on provide the boundary conditions for the landslide instability. Next, human activities and precipitation and so on are the predominant e inducing factors for the instability. The various factors are complement to each other to lead to the development and taking place of the landslide. Based on the above results,this paper uses the SARMA and FLAC methods to calculate and simulate the stability extent of the landslide. The analysis of soil body stress and calculation o the factor of safety factor for the landslide show that although the landslide is in a stable state as a whole, there is the possibility for a partial instability of landslide at the left side of front edge. This analysis result is basically in accordance to the result of the field investigation result . But, in the saturated state, the natural and seismic state, the saturated and seismic state, the probability for a whole instability of the landslide is high.
The paper presents the characteristics of landslide hazards and the style of possible elements at risk at the Baota mountain in Yan'an city. Accordingly, the vulnerability for the landslide hazard is divided for two parts: population vulnerability and economy vulnerability. The sources of risks affecting the safety of live and property are recognized based on the local risk mapping. So, the quantitative analysis is carried out on the factors referring to the vulnerability. In particular, the analysis is also used engineering geological experience. The risk that the local people living at the BaoTa Mountain maybe encounter is assessed. At present, the risk to some of the local people cannot be accepted following the international standard. Landslide monitoring has to be undertaken to have earlier warning for reducing the risk. The paper presents the characteristics of landslide hazards and the style of possible elements at risk at the Baota mountain in Yan'an city. Accordingly, the vulnerability for the landslide hazard is divided for two parts: population vulnerability and economy vulnerability. The sources of risks affecting the safety of live and property are recognized based on the local risk mapping. So, the quantitative analysis is carried out on the factors referring to the vulnerability. In particular, the analysis is also used engineering geological experience. The risk that the local people living at the BaoTa Mountain maybe encounter is assessed. At present, the risk to some of the local people cannot be accepted following the international standard. Landslide monitoring has to be undertaken to have earlier warning for reducing the risk.
This paper adopts the two methods: water absorption of irregular rock in both dry and saturated conditions and cemented coefficient of rock, proposed by Qu Yongxin, to study the swelling potential of mud rock. The mud rock is in some tunnel coal mine in Shanxi. The results show that the mud rock does not swell. On the other hand, the paper examines the mineral composition of the mud rock. It is found that the mud rock has much, non-uniform distributed quartz and iron, as well as kaolinite. The kaolinite is the main clay mineral. The mud rock shows brittle failure when it is compressed under uniaxial and triaxial tests with low confining pressure. Finally,the paper introduces several factors influencing the failure of rock. The factors include mineral composition, configuration and conformation, characteristic of joint or tiny joint surface and extension cranny in rock. This paper adopts the two methods: water absorption of irregular rock in both dry and saturated conditions and cemented coefficient of rock, proposed by Qu Yongxin, to study the swelling potential of mud rock. The mud rock is in some tunnel coal mine in Shanxi. The results show that the mud rock does not swell. On the other hand, the paper examines the mineral composition of the mud rock. It is found that the mud rock has much, non-uniform distributed quartz and iron, as well as kaolinite. The kaolinite is the main clay mineral. The mud rock shows brittle failure when it is compressed under uniaxial and triaxial tests with low confining pressure. Finally,the paper introduces several factors influencing the failure of rock. The factors include mineral composition, configuration and conformation, characteristic of joint or tiny joint surface and extension cranny in rock.
Uses PFC2D to set up the model of reflecting the microstructure of cohesive soil. Then, numerical shear tests with different directions are carried out. The shear stress-strain curves and shear strain-volumetric strain curves are obtained. The elastic modulus, Poisson's ratio, bulk modulus and shear modulus under different directions are calculated from the numerical curves. The shear peak strength of cohesive soil in each direction is further studied. Basically, the peak shear strength reduces from the vertical to the horizontal orientations. The results show the feasibility of using PFC2D to model the anisotropic behavior of cohesive soil with the consideration of its internal micro-structure. Uses PFC2D to set up the model of reflecting the microstructure of cohesive soil. Then, numerical shear tests with different directions are carried out. The shear stress-strain curves and shear strain-volumetric strain curves are obtained. The elastic modulus, Poisson's ratio, bulk modulus and shear modulus under different directions are calculated from the numerical curves. The shear peak strength of cohesive soil in each direction is further studied. Basically, the peak shear strength reduces from the vertical to the horizontal orientations. The results show the feasibility of using PFC2D to model the anisotropic behavior of cohesive soil with the consideration of its internal micro-structure.
An one-dimensional consolidation test under separated loads is conducted to obtain the characteristic creep curves of loess in Yangling Distirct. According to the typical behavior of stress-strain curves of loess under one-dimensional consolidation,an one-dimensional consolidation creep constitutive model is obtained from the relation of parameters and consolidation stress. The relation better simulates the creep characteristics of loess in Yangling District with model test. Besides, based on the experimental results and the secondary consolidation coefficient proposed by Buisman, the relation between the secondary consolidation coefficient and the consolidation stress is obtained. Therefore, a new method of confirming the influence of consolidation stress on the secondary consolidation characteristics is suggested. An one-dimensional consolidation test under separated loads is conducted to obtain the characteristic creep curves of loess in Yangling Distirct. According to the typical behavior of stress-strain curves of loess under one-dimensional consolidation,an one-dimensional consolidation creep constitutive model is obtained from the relation of parameters and consolidation stress. The relation better simulates the creep characteristics of loess in Yangling District with model test. Besides, based on the experimental results and the secondary consolidation coefficient proposed by Buisman, the relation between the secondary consolidation coefficient and the consolidation stress is obtained. Therefore, a new method of confirming the influence of consolidation stress on the secondary consolidation characteristics is suggested.
On the base of un-drained dynamic tri-axial shearing tests. It examines the five influence factors on the dynamic properties of saturated loess, where the loess has its original internal structure. The five factors are the initial consolidated pressure, the over-consolidation ratio, the consolidated ratio, the dynamic shearing stress ratio and the frequency. The results are compared to other references and analyzed in detail. The structure of saturated loess is emphasized. The destroy of the loess's internal structure is a turning point for the dynamic properties. It is reasonable to use plastic strain to describe the change of structure and constitute the supper-pore pressure model. The relevant formulation is also given. On the base of un-drained dynamic tri-axial shearing tests. It examines the five influence factors on the dynamic properties of saturated loess, where the loess has its original internal structure. The five factors are the initial consolidated pressure, the over-consolidation ratio, the consolidated ratio, the dynamic shearing stress ratio and the frequency. The results are compared to other references and analyzed in detail. The structure of saturated loess is emphasized. The destroy of the loess's internal structure is a turning point for the dynamic properties. It is reasonable to use plastic strain to describe the change of structure and constitute the supper-pore pressure model. The relevant formulation is also given.
Geo-hazards have some correlations with rain-time, rainfall and rain-type. For different rain-types, rainfall induced geo-hazards have different characteristics. In this paper, according to rainfall and geo-hazards data, the rainfalls that can induce geo-hazards are classified into three types. They are typhoon rainfall, sustained rainfall and regional rainstorm. The characteristics of geo-hazards induced by different rainfall-types are different. Typhoon rainfall induced geo-hazards have the characteristics of hazards and rainfall consistently. It is consistent in time and space. The hazards are almost clustery accruing, shallow sliding or rock-fall. For sustained rainfall, geo-hazards have the hysteresis action with small rain-intensity. But for inducing new hazards, it needs larger rainfall after hazards occurred. Geo-hazards induced by regional rainstorm often occur in the day and space as same as the rainfall. Geo-hazards have some correlations with rain-time, rainfall and rain-type. For different rain-types, rainfall induced geo-hazards have different characteristics. In this paper, according to rainfall and geo-hazards data, the rainfalls that can induce geo-hazards are classified into three types. They are typhoon rainfall, sustained rainfall and regional rainstorm. The characteristics of geo-hazards induced by different rainfall-types are different. Typhoon rainfall induced geo-hazards have the characteristics of hazards and rainfall consistently. It is consistent in time and space. The hazards are almost clustery accruing, shallow sliding or rock-fall. For sustained rainfall, geo-hazards have the hysteresis action with small rain-intensity. But for inducing new hazards, it needs larger rainfall after hazards occurred. Geo-hazards induced by regional rainstorm often occur in the day and space as same as the rainfall.
The effects of pore-water pressure on the apex post characteristics of stress-strain curves for rock mass are analyzed from the macroscopic and microcosmic mechanisms. An apex post modulus Epost which indicates the effect of pore-water pressure on stress-strain curves transition is defined. Bycombining with the stiffness criterion of landslide, the effect of pore-water pressure on stress-strain curves apex post slope is analyzed. Along with the increase of pore-water pressure, the apex post curve slope becomes steep, and the apex post stiffness increases. The homogeneity and brittleness of slide surface medium increases and the stiffness ratio k decreases. When the system conditions don't change, corresponding with k=1, the pore-water pressure has a critical value pwcritical. When the pore-water pressure surpasses the value pwcritical, landslide is prone to be induced by rainfall. Consequently rainfall and other condtion changes have important effects inducing landslides. The effects of pore-water pressure on the apex post characteristics of stress-strain curves for rock mass are analyzed from the macroscopic and microcosmic mechanisms. An apex post modulus Epost which indicates the effect of pore-water pressure on stress-strain curves transition is defined. Bycombining with the stiffness criterion of landslide, the effect of pore-water pressure on stress-strain curves apex post slope is analyzed. Along with the increase of pore-water pressure, the apex post curve slope becomes steep, and the apex post stiffness increases. The homogeneity and brittleness of slide surface medium increases and the stiffness ratio k decreases. When the system conditions don't change, corresponding with k=1, the pore-water pressure has a critical value pwcritical. When the pore-water pressure surpasses the value pwcritical, landslide is prone to be induced by rainfall. Consequently rainfall and other condtion changes have important effects inducing landslides.
Seawater intrusion is a kind of geological disaster due to the effect of human activities associated with natural environment change. The background of geological environment is complex in Fujian coastal zones. The seawater intrusion can be divided into estuarine type, aquifer type and along fault zone type according to its ways. Finally, the paper points out to pay attention to the disaster of seawater intrusion in Fujian Province to avoid the deterioration of economic activities and the natural environment. Seawater intrusion is a kind of geological disaster due to the effect of human activities associated with natural environment change. The background of geological environment is complex in Fujian coastal zones. The seawater intrusion can be divided into estuarine type, aquifer type and along fault zone type according to its ways. Finally, the paper points out to pay attention to the disaster of seawater intrusion in Fujian Province to avoid the deterioration of economic activities and the natural environment.
This paper uses landslide and micropile model tests to examine the control mechanism, sliding force and the damage form of single micropile for landslide reinforcement. The test results show that the micropile can enhance the stability of landslide effectively. After the landslide is reinforced with micropile, the stability coefficient of the landslide can be increased from 0.96 to 1.35. The landslide pushing force and the landslide bedding resistance are found to have triangle distribution. The focus of the resultant force approaches to the sliding face. The micropile damages near the sliding face. The damage forms of micropile can be defined as cutting and bending failures. This paper uses landslide and micropile model tests to examine the control mechanism, sliding force and the damage form of single micropile for landslide reinforcement. The test results show that the micropile can enhance the stability of landslide effectively. After the landslide is reinforced with micropile, the stability coefficient of the landslide can be increased from 0.96 to 1.35. The landslide pushing force and the landslide bedding resistance are found to have triangle distribution. The focus of the resultant force approaches to the sliding face. The micropile damages near the sliding face. The damage forms of micropile can be defined as cutting and bending failures.
As a rule, the thickness of wall painting plaster in Tibet is less than 10 cm. The ground penetrating radar (GPR) is applied to detection of delamination beneath wall painting plaster, It is quite a challenge task to remove directly the coupled noise waves in the radar profiling. So, size of the delamination can be determined accurately. Replica of Tibetan wall painting plaster is made and regular voids with different depths and sizes are set inside it. Then, the forward modeling detection is carried out in the replica in order to get appropriate parameters for acquisition of radar data, to find effective filters for signal processing, and to compare the performance of different antennas. Specifically to the RAMAC/GPR and its accessory software of Ground Vision, it is suggested that the depth of time window be about 3 ns and sampling frequency not less than 142 GHz, and that band pass filter and background subtraction are the two most useful filters in signal processing. When the antenna and the fine plaster are well coupled, both antennas at nominal center frequency of 1.6 GHz and 2.3 GHz are capable of detecting void located at a depth of about 3 cm and a size of around 2 cm. The vertical resolution limit of 1.6 GHz antenna is near 0.5 cm in size. As a rule, the thickness of wall painting plaster in Tibet is less than 10 cm. The ground penetrating radar (GPR) is applied to detection of delamination beneath wall painting plaster, It is quite a challenge task to remove directly the coupled noise waves in the radar profiling. So, size of the delamination can be determined accurately. Replica of Tibetan wall painting plaster is made and regular voids with different depths and sizes are set inside it. Then, the forward modeling detection is carried out in the replica in order to get appropriate parameters for acquisition of radar data, to find effective filters for signal processing, and to compare the performance of different antennas. Specifically to the RAMAC/GPR and its accessory software of Ground Vision, it is suggested that the depth of time window be about 3 ns and sampling frequency not less than 142 GHz, and that band pass filter and background subtraction are the two most useful filters in signal processing. When the antenna and the fine plaster are well coupled, both antennas at nominal center frequency of 1.6 GHz and 2.3 GHz are capable of detecting void located at a depth of about 3 cm and a size of around 2 cm. The vertical resolution limit of 1.6 GHz antenna is near 0.5 cm in size.
When the diversion tunnel of Ming Tombs pumped storage station in Beijing passed through the fragmented rock mass, landslip happened in the early stage of excavation because of bad geological conditions. Displacement monitoring was performed in time after landslip. The monitored results showed that support structure composed of anchoring shotcrete with wire mesh and steel arch frame used by the original design had great deformation, especially in the side walls. According to the monitored results, supporting scheme for the diversion tunnel was modified significantly. For example, steel arch frames and reinforced bars for the wire mesh were increased. Sprayed concrete was thickened. The inverted arch was added for the tunnel floor. After the above measures were constructed, the displacement of the tunnel has decreased and the deformation has stabilized. The displacement and deformation have reached the design and operation requirements. The successful design illustrates that the monitoring during construction for design change is very important under complicated engineering geologic conditions. Design of other tunnels can draw lessons from this case study. When the diversion tunnel of Ming Tombs pumped storage station in Beijing passed through the fragmented rock mass, landslip happened in the early stage of excavation because of bad geological conditions. Displacement monitoring was performed in time after landslip. The monitored results showed that support structure composed of anchoring shotcrete with wire mesh and steel arch frame used by the original design had great deformation, especially in the side walls. According to the monitored results, supporting scheme for the diversion tunnel was modified significantly. For example, steel arch frames and reinforced bars for the wire mesh were increased. Sprayed concrete was thickened. The inverted arch was added for the tunnel floor. After the above measures were constructed, the displacement of the tunnel has decreased and the deformation has stabilized. The displacement and deformation have reached the design and operation requirements. The successful design illustrates that the monitoring during construction for design change is very important under complicated engineering geologic conditions. Design of other tunnels can draw lessons from this case study.
In accordance with engineering practice of Jinchuan Nickel Mine in Gansu Province, China, this paper studies the method and process of developing ground surface movement information management and analyzing system for mines. The system is a GIS based secondary development. The paper discusses the structure and functions of the system. The system contains three modules: management of ground surface movement information, analysis and evaluation of ground surface movement, and ground surface movement forecast. The system makes the best of powerful information management and spatial analyzing capabilities of GIS, and can carry out the analysis and evaluation of ground surface movement by combining Surfer 8.0. And in the module of forecast, using the technique of MATLAB 6.5 program with VB 6.0, the system can achieve the ANN prediction model for GPS monitoring data. The study results shall improve management and analyzing efficiency for ground surface movement information in Jinchuan Nickel Mine, and can be used in developing the information system of ground surface movement in other mines. In accordance with engineering practice of Jinchuan Nickel Mine in Gansu Province, China, this paper studies the method and process of developing ground surface movement information management and analyzing system for mines. The system is a GIS based secondary development. The paper discusses the structure and functions of the system. The system contains three modules: management of ground surface movement information, analysis and evaluation of ground surface movement, and ground surface movement forecast. The system makes the best of powerful information management and spatial analyzing capabilities of GIS, and can carry out the analysis and evaluation of ground surface movement by combining Surfer 8.0. And in the module of forecast, using the technique of MATLAB 6.5 program with VB 6.0, the system can achieve the ANN prediction model for GPS monitoring data. The study results shall improve management and analyzing efficiency for ground surface movement information in Jinchuan Nickel Mine, and can be used in developing the information system of ground surface movement in other mines.
Uses a reflected wave method and an oven dry method to estimate soil water content. Experimental study is carried out. The reflected wave method is based on the ground penetration radar technique. The empirical equation of experimental silt is obtained via curve fitting of soil water content versus dielectric constant. Comparative analysis shows that the classical Topp formula has a good serviceability in certain water content rang. An empirical formula is proposed in this paper. It has a wider range of estimating soil water content and a higher estimate accuracy than the classical Topp formula. This study indicates that the empirical formula is necessary for different types of soils and will help to improve the accuracy of estimation of soil water content with ground penetrating radar technique. Uses a reflected wave method and an oven dry method to estimate soil water content. Experimental study is carried out. The reflected wave method is based on the ground penetration radar technique. The empirical equation of experimental silt is obtained via curve fitting of soil water content versus dielectric constant. Comparative analysis shows that the classical Topp formula has a good serviceability in certain water content rang. An empirical formula is proposed in this paper. It has a wider range of estimating soil water content and a higher estimate accuracy than the classical Topp formula. This study indicates that the empirical formula is necessary for different types of soils and will help to improve the accuracy of estimation of soil water content with ground penetrating radar technique.
Excavating tunnel under existing passenger transferring subway station is of very importance. Stringent risk assessment and control must be applied to keep operation of the subway station safely. The paper mainly introduces the risk assessment and the third-party monitoring measurement of a new tunnel construction underneath a Beijing Subway Wanshou Road Station. This station is a passenger transferring subway station. The tunnel construction might result the settlement of the subway station structure and make the rail distort. It might impact the safety of station operation. The project used methods of structure measuring, construction numerical simulation and the third-party monitoring measurement. The results show that the station was safe and was operated safely. The results presented in the paper may give a good reference to other similar projects. Excavating tunnel under existing passenger transferring subway station is of very importance. Stringent risk assessment and control must be applied to keep operation of the subway station safely. The paper mainly introduces the risk assessment and the third-party monitoring measurement of a new tunnel construction underneath a Beijing Subway Wanshou Road Station. This station is a passenger transferring subway station. The tunnel construction might result the settlement of the subway station structure and make the rail distort. It might impact the safety of station operation. The project used methods of structure measuring, construction numerical simulation and the third-party monitoring measurement. The results show that the station was safe and was operated safely. The results presented in the paper may give a good reference to other similar projects.
The permeability of rock and soil aggregates (RSA) is important for engineering construction, prevention and treatment of landslides in RSA. This paper gives a summary of the previous studies of the rockfill permeability test apparatus. The Tsinghua University test system is special for its recycle of water. The Hohai University test instrument is horizontal. Its lifter has the accurate control of the water level for its higher and lower water supply. Nanjing Hydraulic Research Institute studied the influence of water board, sample preparation methods and anti-seepage of the wall to the permeability test. The Luo Yuzai permeability test apparatus is special at its capability for providing the continuous high-pressure water without air. Using self-made permeability test instrument, Zhou Zhong and others from Central South University studied the permeability coefficient and its influencing factors of RSA. On the basis of previous studies, we have developed a servo-control rock and soil aggregate permeability test apparatus. The apparatus can servo-control the velocity and stress of the water supply, provide high-pressure ( 2MPa) and adjust the velocity of the seepage. It is convenient to operate. The apparatus can study the permeability of the RSA successfully. The permeability of rock and soil aggregates (RSA) is important for engineering construction, prevention and treatment of landslides in RSA. This paper gives a summary of the previous studies of the rockfill permeability test apparatus. The Tsinghua University test system is special for its recycle of water. The Hohai University test instrument is horizontal. Its lifter has the accurate control of the water level for its higher and lower water supply. Nanjing Hydraulic Research Institute studied the influence of water board, sample preparation methods and anti-seepage of the wall to the permeability test. The Luo Yuzai permeability test apparatus is special at its capability for providing the continuous high-pressure water without air. Using self-made permeability test instrument, Zhou Zhong and others from Central South University studied the permeability coefficient and its influencing factors of RSA. On the basis of previous studies, we have developed a servo-control rock and soil aggregate permeability test apparatus. The apparatus can servo-control the velocity and stress of the water supply, provide high-pressure ( 2MPa) and adjust the velocity of the seepage. It is convenient to operate. The apparatus can study the permeability of the RSA successfully.
This paper presents the statistics and analysis on the received and funded proposals for grants from National Natural Science Foundation of China in engineering geology in 2009. The number of the received proposals increases fast. The quality of the proposals has yet to be improved. The distribution of researchers in basic studies is unevenly distributed in different institutions. It is suggested to pay more attention to the development of young scientific talents in engineering geology. This paper presents the statistics and analysis on the received and funded proposals for grants from National Natural Science Foundation of China in engineering geology in 2009. The number of the received proposals increases fast. The quality of the proposals has yet to be improved. The distribution of researchers in basic studies is unevenly distributed in different institutions. It is suggested to pay more attention to the development of young scientific talents in engineering geology.